Physics – Condensed Matter – Superconductivity
Scientific paper
2011-05-05
Physics
Condensed Matter
Superconductivity
4 pages, 7 figures, submitted to J. Phys. Soc. Jpn, (modified version)
Scientific paper
Specific heats and transport quantities of the LaFe1-yNiyAsO0.89F0.11 system have been measured, and the results are discussed together with those reported previously by our group mainly for LaFe1-yCoyAsO0.89F0.11 and LaFeAsO0.89-xF0.11+x systems. The y dependence of the electronic specific heat coefficient gamma can basically be understood by using the rigid-band picture, where Ni ions provide 2 electrons to the host conduction bands and behave as nonmagnetic impurities. The superconducting transition temperature Tc of LaFe1-yNiyAsO0.89F0.11 becomes zero, as the carrier density p (=2y+0.11) doped to LaFeAsO reaches its critical value p_c_ ~0.2. This p_c_ value of ~0.2 is commonly observed for LaFe1-yCoyAsO0.89F0.11 and LaFeAsO0.89-xF0.11+x systems, in which the relations p = x+0.11 and p = y+0.11 hold, respectively. As we pointed out previously, the critical value corresponds to the disappearance of the hole-Fermi surface. These results indicate that the carrier number solely determines the Tc value. We have not observed appreciable effects of pair breaking, which originates from the nonmagnetic impurity scattering of conduction electrons and strongly suppresses T_c_ values of systems with sign-reversing of the order parameter over the Fermi surface(s). On the basis of the results, the so-called s_+-_ symmetry of the order parameter with the sign-reversing is excluded.
Itoh Masayuki
Kawamata Takayuki
Kobayashi Yoshiaki
Sato* Masatoshi
Satomi Erika
No associations
LandOfFree
Study of Ni-doping Effect of Specific Heat and Transport Properties for LaFe1-yNiyAsO0.89F0.11 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Study of Ni-doping Effect of Specific Heat and Transport Properties for LaFe1-yNiyAsO0.89F0.11, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Study of Ni-doping Effect of Specific Heat and Transport Properties for LaFe1-yNiyAsO0.89F0.11 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-690148